In fact, apart from spats over NATO commands, things have never looked so good, with policy experts citing a catalogue of examples of EU-US cooperation.

In the former Yugoslavia, where the two have been accused of causing the war to drag on as Serbs and Bosnians played the allies off against each other, governments on both sides of the Atlantic are working in sync.

“We are extremely close, almost identical on the major principles regarding Serbia, Bosnia and Kosovo,” said an American diplomat. “There are differences, but they are nuances, such as timing, the balance between carrots and sticks, which carrots should be linked to which moves, and where decisions should be taken or announced.”There is a real risk of a dispute in the summer of 1998, when the SFOR (international peace implementation force) mandate runs out. But for the next 12 months, while there will be continual debate on small points, officials say they foresee no substantive clashes.

Their counterparts in Cyprus sing the same song.

“We are cooperating very well. Everybody is sharing – it is unbelievable. When something really starts happening, ask me again, but for now we are best buddies,” said one.

But things are not as rosy when it comes to NATO, a breeding ground for EU-US disputes over recent months.

The gravest of these has been, and continues to be, the fight for command of NATO activities in the Mediterranean. Paris wants the post of commander-in-chief southern Europe to go to a European. But with theUS sixth fleet sailing those waters, Washington is adamant that it should go to an American.

Paris pinned its re-entry into NATO’s integrated military structure on winning that fight and even Pamela Harriman, the late US ambassador to France whose relations with French President Jacques Chirac and his government were warm and cordial, could not smooth over this problem.

Another potential fly in the ointment is the growing relationship between the Union and Asia. Paris and other EU capitals have made much play of their closer ties with the region this year, prompting speculation that such bragging could irritate Washington.

But US officials say that here, too, there are positive feelings about European policy.

They are pleased that the Union has joined the US-Japan energy programme on the Korean peninsula (KEDO), and they are working well with their EU partners in the Asian Regional Forum – that continent’s equivalent of the Organisation for Security and Cooperation in Europe (OSCE).

Its attempts in recent months to draw a link between trade and labour standards have set the US administration at loggerheads with some EU member states, but others agree with Washington that the two should be considered together.

China will always be a big test for western governments, but most Union countries and the US have agreed to pressure Beijing on its human rights record, and American officials say they are pleased to see that “the EU is starting to broaden its scope in Asia to give more importance to political issues”, rather than just commercial ones.

“Europe wants to be an Asian player and US policy is to encourage joint action with the Europeans in all areas,” said one official. “We do not want to get into a situation in which commercial rivalry between the Union and the US allows Asians to play us off against each other.”Perhaps the area with the biggest potential for EU-US rivalry is the Middle East. But Union envoy Miguel Moratinos and his US counterpart Dennis Ross have worked so well together lately that officials describe the policies they are pursuing as “real synergy”.

If the peace process survives, and Syria and Lebanon start to take part in earnest, the potential for transatlantic division will grow. France’s solo diplomacy in Beirut often irritates Americans.

“The whole Middle East is so loaded that things go wrong if any one party goes off and does something the other does not like,” said one expert.

But for now, the prognosis is good. “There are always going to be differences, even among best friends, but we are in sync,” he said, adding wryly: “The day that the EU and the US absolutely agree on every issue, please call me.”